It just stopped and no-one knows why [Archive]

Oakie

31st March 2005, 11:39

White trash

31st March 2005, 11:51

Any ideas anyone?

Yup.

Trade it quick smart on a Gixxer.

Motoracer

31st March 2005, 12:02

Yup.

Trade it quick smart on a Gixxer.

There's a reason why you are in sales and not workshop, isn't there?

White trash

31st March 2005, 12:03

There's a reason why you are in sales and not workshop, isn't there?

Yup. I'm a mechanical spastic. And I've already worked in that department.

Ixion

31st March 2005, 12:06

Toodling down the highway last week and the bike ('92 Honda CB400SF) just stopped. No backfire, no rough running ... just wound down to a halt. (Yes, plenty of fuel in the tank.) I cranked it over but gave no indication of firing up again. I gave it about 10 minutes rest to think about it what it had done and then cranked it over and it fired up good as gold and we toodled on down the highway again ... for about a kilometer when we had the same stoppage. Cranked again to no immediate avail but after another 10 minutes waiting she started up, ran as normal... and we got another kilometer. Long story short ... we got it picked up but the mechanic at the shop we took it to has been unable to diagnose the fault. (They left it idling with the idea of seeing what happend when it stopped of it's own accord but of course it just kept on ticking over sweetly!) Naturally my first thought was the fuel supply but that seems OK. He's looking at the electrics but can't seem to find any faults.

Any ideas anyone?

Pretty much has to be either fuel flow or something related to temperature. No sign of overheating ? What happens if you ride slow at very low revs ? Do you get more than 1 km when starting from cold ? Tried taking the fuel cap off when it happens? Blocked vent pipe ? Dirty fuel? Dud coils ? . Sticky pivot on the CB (probably don't have one though) . Can you make it happen, turn off fuel and drop a carby bowl (assume this model has carbs of course. If its injected then it's any mans guess and probably a job for the experts) to see if there's fuel there. Make it happen, whip a spark lead off fast , stick it on a spare plug and check for spark . Older type bikes, if I had to look at one thing first it would be either fuel filter or coil. Later ones with electronic mumbo jumbo ? Call in the mumbo jumbo witch doctor

Drunken Monkey

31st March 2005, 12:07

Well I had 2 toyotas with the same symptom, it was the igniter both times. Don't know if your bike has an igniter before the coils though...

2 schmoke

31st March 2005, 12:10

thats exactly what happened to me the other day.. my bike just stopped.. i let it rest and it went well for 10 minutes then just stopeed again. so we took off the carburettor ( cant spell it) and looked inside and there was a shit load of crap inside.. which was evidently blocking the jets, so we cleaned that out ann i goes fine now

Sniper

31st March 2005, 12:22

My deduction is its broken

Motu

31st March 2005, 12:30

While it was stopped and wouldn't start - you did something important that made it go again....retrace your every movement.Did you pick your nose?,Which nostril,which finger of what hand? Witch way did you walk around the bike..clockwise or widershins? did you recite any incantions? It's all in the details - but somehow you did something that made your bike go again...recreate the actions and you have the first step into the magical world of motorcycles...

BUBBLE

31st March 2005, 12:40

Sounds like fuel, check filter and tank breather, try the fuel tap both On and Reserve.

Yep....go the Suzuki's.

Oakie

31st March 2005, 13:10

A week earlier it stopped on me after 1 km but then went fine for the next 300km. This time we'd done about 30km.
At the roadside I thought it had to be fuel. I turned the petrol tap off, took the bowl off the bottom of the tap and there was (clean) fuel there. When I turned the tap to 'on' and then 'reserve' no petrol flowed out from the tap which surprised me a little ... although perhaps it needs to be sucked rather than just flowing freely?
There were no signs of overheating. Liquid cooled and the needle hardly moved from the chilly end of the temp guage. No hot smell.
Thought it may have been electrics and something breaking down under load but the regularity of the distance between stopping still makes me think 'fuel'.

Blocked vent pipe creating a vacuum in the tank sounds interesting. I noticed the other day when it was sitting in the heat, the expanded vapours were venting from somewhere under the seat rather than the petrol cap which is where I'm used to it venting from. Hmm. Lunchtime. I might go and annoy the mechanic with that idea.
Cheers

vifferman

31st March 2005, 13:20

Blocked vent pipe creating a vacuum in the tank sounds interesting. I noticed the other day when it was sitting in the heat, the expanded vapours were venting from somewhere under the seat rather than the petrol cap which is where I'm used to it venting from. Hmm. Lunchtime. I might go and annoy the mechanic with that idea.
Cheers
Sounds like that could possibly be the fuel tap, if it's a vaccuum-operated one. If it is, and the diaphragm is bruk, it will leak and smell, as there's a small vent on the tap mechanism on the outside of the diaphragm chamber. It would also explain the bike stopping, as the diaphragm isn't being pulled out by the manifold vaccuum.

If it's not a vaccuum-operated tap, I dunno. :spudwhat:
But as others have said, venting's important. VTRs f'rinstance, have a habit of stopping if there's grunge in the end of the vent hose, as there's no fuel pump to force petrol through and a slight lacking in venting stops the thirsty big carbs getting enough juice - OK at idle, but not at road speeds.

If it's not fuel, then an electrical fault can often show up only when the bike's hot. An R/R or alternator fault seems most unlikely, as then the battery would be flat, but faulty coils often crap out when hot.

Ixion

31st March 2005, 13:21

I turned the petrol tap off, took the bowl off the bottom of the tap and there was (clean) fuel there. When I turned the tap to 'on' and then 'reserve' no petrol flowed out from the tap which surprised me a little ... although perhaps it needs to be sucked rather than just flowing freely?

Very suspicious that.I have known bikes that had a diaphragm on the tap so that the fuel didn't flow out in a crash. Could be your problem. In thory suction from the engine works on the diaphragm to open the flow (enough fuel in carb and tap bowls for initial start).

Diaphragm wrinkles/holes etc, won't open properly. Lets a little fuel flow through, enough for idling but with an open throttle the bowl on the carb empties after a while. Then you have to wait until the slow piddle getting through the tap fills the carb again

Definately sounds like fuel , get a mecho to check the tap (or bypass it temporarily)

vifferman

31st March 2005, 13:27

Very suspicious that.I have known bikes that had a diaphragm on the tap so that the fuel didn't flow out in a crash. Could be your problem. In thory suction from the engine works on the diaphragm to open the flow (enough fuel in carb and tap bowls for initial start).
On my VF500 I had problems with the tap in that sometimes the No.1 (or whatever) cylinder whose intake manifold it was connected to would run REALLY rich as it sucked extra fuel directly from the tap. And every so often, the hose would crack (petrol going into it probably didn't help) and it would run extra lean.
Stupid bloody thing...

Riff Raff

31st March 2005, 13:30

My deduction is its broken

My deduction is that it doesn't love you anymore! Have you been giving it lots of TLC prior to the event, have you told it that you love it recently, have you given it a nice warm garage to sleep in? If the answer is yes to all these questions, then it's a cantankerous bitch and needs to be traded on a Gixxer (do I get commission for helping you with a sale White Trash??)

BM-GS

31st March 2005, 13:36

I had a KMX125 do that once. It turned out to be the kill-switch, which hadn't worked at all for the preceding 6 months, and only did sporadically after this event.

Still, I had a pleasant 1/2 hour in the pub contemplating the situation & canvassing opinions from the locals. A bloke with a KMX125 solved the problem and gave me a good tip on a shortcut home.

Happy days....

Oakie

31st March 2005, 13:53

My deduction is that it doesn't love you anymore! Have you been giving it lots of TLC prior to the event, have you told it that you love it recently, have you given it a nice warm garage to sleep in? If the answer is yes to all these questions, then it's a cantankerous bitch and needs to be traded on a Gixxer (do I get commission for helping you with a sale White Trash??)

I haven't told it that I love it yet because we're just friends. I've only had it two weeks and I don't like to rush into relationships. I have however given it TLC and given it a nice warm garage to sleep in ... although I have neglected to close the door from time to time. (Perhaps it's just jealous that my wife is always on the back and we don't get time alone together)

OH MY GOD. Cantankerous Bitch. That's what the 'CB' stands for. Of course! (I'm screwed)

inlinefour

31st March 2005, 14:30

Yup.

Trade it quick smart on a Gixxer.

Why go backwards in bikes?
Rather if you want to trade, trade up to a Fireblade. :niceone:
Actually the bike might be the same as mine, if thats the case then its a 1992 CB400f2, look at my profile picture of my ride.
Just had some electrical problems with mine, ended up replacing the voltage regulator. However yours sounds like something completely different. More like something is wrong when hot and comes right when it cools down?
Pretty hard to diagnose these things without looking at the bike in question. My advice is like anything else in life. If you go somewhere looking for answers and you get the "err, I don't know" treatment. Tell to get stuffed and take the bike elsewhere. If they look hard enough, with the right equipment then they will eventually find what is wrong and fix it...

Hooks

31st March 2005, 14:42

It's just a honda !! :shake: .. Suzukis just keep going !! I treat my old girl badly and she just never quits ... no gargre ... nothing !! :banana: all she ever does is use up tyres and throw things at other bikes :whistle: ..... Mind you every now & then I have to put gas in her .... which could be your problem ... it can't flow if there's nothing in the tank but cobwebs !! :lol: :killingme

James Deuce

31st March 2005, 14:43

This may be a red herring, but it is a Honda and they are reknowned for it. Get the Regulator/Rectifier checked. My FIAT ( I know - it's a car) does the exact thing you are saying when the heat sink falls off. Which it's done twice. The heatsink falls off, the reg/rec is on the back of the alternator, the back of which is almost touching the block. The car would stop running, I'd leave it for a while, and once the reg/rec had cooled down, off we went. I know that the Honda ones don't have a heatsink anyway, but I think it may be worth checking.

vifferman

31st March 2005, 15:00

This may be a red herring, but it is a Honda and they are reknowned for it. Get the Regulator/Rectifier checked.
Doesn't quite fit with the symptoms, especially given the battery's not running flat. Yes, the R/R can play up when hot, but you'd expect some other electrical indications, like the aforementioned flat battery, or electrical components blowing up (if the R/R failed in 'over-supply mode').

James Deuce

31st March 2005, 15:05

inlinefour

31st March 2005, 15:08

Doesn't quite fit with the symptoms, especially given the battery's not running flat. Yes, the R/R can play up when hot, but you'd expect some other electrical indications, like the aforementioned flat battery, or electrical components blowing up (if the R/R failed in 'over-supply mode').

Mine blew the bulbs and boiled the battery dry. Get the engine running and grab a multi meter. Put em on the battery terminals and give it some throttle. If the voltage increases with increased revs then the voltage regulator is nackered. But like said before it sounds like its something else. Oh and for the comments about "Honda are well known for this", wrong as its Honda jap imports are well known for it :shifty:

James Deuce

31st March 2005, 15:10

"Honda are well known for this", wrong as its Honda jap imports are well known for it :shifty:

Hee hee. Sorry Honda.

Had a mate with a 1990 VFR750 that went through two in 5000kms from brand new, but I've owned two Hondas and they were both brilliant at everything and reliable as anything I've ever owned.

31st March 2005, 15:13

Hee hee. Sorry Honda.

Had a mate with a 1990 VFR750 that went through two in 5000kms from brand new, but I've owned two Hondas and they were both brilliant at everything and reliable as anything I've ever owned.
Yeah, I've had a good run with all the bikes I have owned..
2 kwakas, 1 yammy and a honda...all good bikes... handled the thrashings and the droppings and the crashings and the vomitings

inlinefour

31st March 2005, 15:14

Hee hee. Sorry Honda.

Had a mate with a 1990 VFR750 that went through two in 5000kms from brand new, but I've owned two Hondas and they were both brilliant at everything and reliable as anything I've ever owned.

But only one jap import, hence only one problem that was quickly fixed with an after market part... :2thumbsup

vifferman

31st March 2005, 15:38

Mine blew the bulbs and boiled the battery dry.
R/R failure in 'over-supply mode'. They don't all fail like that - my two were in "under-supply, run the battery flat till there's no juice left for sparks mode".

Get the engine running and grab a multi meter. Put em on the battery terminals and give it some throttle. If the voltage increases with increased revs then the voltage regulator is nackered.
Almost right.
The voltage should be around 12-ish at idle, and increase to a maximum of anywhere from 13.5V to 15.xV (depending on the Honda model and R/R model, and how flat the battery is/was) at above 5.5k rpm.
And if the R/R is knackeried, the voltage may increase initially, then decrease again as the revs rise (been there, had that).

But like said before it sounds like its something else.
Indeed - I vote for the fuel tap.

Oh and for the comments about "Honda are well known for this", wrong as its Honda jap imports are well known for it :shifty:
Mebbe.
Explains my (Jap import) VFR750, but not my VTR1000, nor all the other failed R/Rs on Hondas scattered across the globe.

What does explain those is Honda insisting on fitting too thin wiring and puny R/Rs, and failing to acknowledge a problem, despite the failures, and despite better R/Rs being available from their suppplier, Shindengen.

inlinefour

31st March 2005, 15:57

I guess that for those who know how to apply the fix will have plenty of bikes to choose from that need a little work and cost less then? :msn-wink:
I guess its like blaming the spoon for so many fat bastards in the world...

vifferman

31st March 2005, 16:23

I guess that for those who know how to apply the fix will have plenty of bikes to choose from that need a little work and cost less then? :msn-wink:
That'd be schweeet if "those who know" were the same people as "those with cash". :confused:
The fix isn't hard, so I used the two I did an excuse to Do It Properly, and did a little rewiring and relocating while I was at it.
It's ferkin frustrating though. My VF500 gave me no electrical problems at all in the 6.5 years I owned it (still had the same battery in it), so I thought "Hah! It'll never happen to me!" :doh:
After doing the VFR, I had no idea the VTRs were similarly afflicted, and was pissed off having to do that as well. Because I wasn't aware they had R/R problems, I bought a new battery, probably unnecessarily (like the one I bought for the VFR, before finding out it was the R/R).

One of the best things you can do if you own a Honda is buy a small voltmeter, and fit it on the instrument panel. Helped me to diagnose the problem on the VTR, after thinking it was the too large headlight bulb sucking too many ergs from the too small battery....

BNZ

31st March 2005, 18:41

inlinefour

31st March 2005, 18:57

I had an FXR for a very short while and it had exactly the same issues - even did it to me heading up the harbour bridge one night :angry2: We were pretty sure it was the coil, as a bit of coil "encouragement" involving a hammer or other heavy object used to kick her back into life. If you can just sell the thing!!! They are not worth spending money on!

I disagree there as often it does not cost that much to fix the problem, especially when compared to getting another bike. It does not allways pay to throw yer toys away, but hey some of us will be happy for you to do so :niceone:

BUBBLE

1st April 2005, 00:30

Dont forget that when the tap is unbolted from the tank there is a small pipe for saving an amount of fuel for reserve. This is normally a fine plastic mesh which can also clog. Which could explain why no fuel came out when you removed the bottom bowl off the tap.
My VFR400 (yes another old honda) had a common problem of rust in the tank. I got sick of the fuel tap blocking with rust and crud so I used a tank sealer kit. Available from PPC in Palmy North or anywhere else that supplies products like POR15 paint. Here is a link with details of the tank sealer kit. http://www.por15.co.nz/por_products/motorcycle_tank_repair_kit.htm

What?

1st April 2005, 06:33

Quick test for fuel flow - remove the hose from the tap. Hold a few inches of garden hose in its place to direct any fuel into a bucket and open the tap. Try both main and reserve positions. You have fuel? If no, open the filler cap. If you have flow now, the vent is blocked. I am pretty sure the vent is built in to the filler cap on your bike. No flow either way, your tap, or the gauze filters are blocked. Remove the tap (empty the tank first!) and give it a clean.
If fuel flow here is not a problem, then the carbs need to come off to clean the needle valves. Could be just not allowing quite enough fuel through to keep the bowls full, but the way you describe it I don't think the answer lies here.
Next simple test is to put new spark plugs in. Check you have the correct plugs also, as this may be the problem.
Still doing it? could be the coils, but I would expect only one to go, meaning the bike would still go, just not very well. Reg/Rec is now looking likely, as is some expenditure.
Good luck.

wildcat_lgf

1st April 2005, 14:07

[QUOTE=vifferman]Sounds like that could possibly be the fuel tap, if it's a vaccuum-operated one. If it is, and the diaphragm is bruk, it will leak and smell, as there's a small vent on the tap mechanism on the outside of the diaphragm chamber. It would also explain the bike stopping, as the diaphragm isn't being pulled out by the manifold vaccuum. [QUOTE]

Yeah just to add my 2cents worth. My mates '92 CBR600F2 did the exact same thing, I'd agree with vifferman that its likely the fuel supply. Turned out to be the diaphram wasn't sealing properly, simple solution, cheap to fix, and if I were a betting man (hooray for G.A. :grouphug: ) I would put money on it being the same with yours. Best option would be check the diaphram and see if it sealing properly, then pick up a 'new' one from a wreckers.

Good luck to ya,

Oakie

1st April 2005, 19:46

Hi
I've got the bike back and I'm holding my breath. They ran it for 30 km and it didn't stop so they were unable to establish exactly what the fault was. They've tested the electrics and found no problem. They've gone through the fuel system...checked the filters, checked out the tap, found a bit of crud in the tank and cleaned up the end of the breather which was perished but apart from that they found nothing obvious.
No charge for any of this (including the pickup from 30km out of town) as it's still under warranty. Good to know some dealers are happy to look after you after they've got your money. (Oh OK ... yay for 'Sportzone Suzuki'.)
I'm going to ride it around as much as I can over the weekend and just see how things go ... (but I don't think I'll be leaving the city limits just yet).

Cross your fingers for me folks and thanks for all the really helpful feedback. I'm sure I'l be reviewing it all if I grind to a halt again.

Cheers

saiko

1st April 2005, 21:45

On my VF500 I had problems with the tap in that sometimes the No.1 (or whatever) cylinder whose intake manifold it was connected to would run REALLY rich as it sucked extra fuel directly from the tap. And every so often, the hose would crack (petrol going into it probably didn't help) and it would run extra lean.
Stupid bloody thing...

Sacrilege!